Wellhofer Loft hatch

Certified airtight and pre-insulated attic door from Wellhofer.


For advice on which airtightness product is best for your project, please contact us on 01484 461705.

  • Certified airtight (Class 4 airtightness) and pre -insulated attic door providing homeowners and specifiers with the optimum level of thermal performance and airtightness.
  • Certified and tested under extreme climate conditions equivalent to that required for external doors on buildings; to EN 1121.
  • Ideal for both new build and retrofit projects
  • Independent airtightness sealing system which seals the hatch frame to the surrounding timber joists, noggins or the adjacent airtightness and vapour control layer.
  • The airtight seal of the hatch door is maintained by means of a pre-stressed spring which ensures the door remains airtight, even when a blower door test is carried out. This spring is full adjustable to the homeowner’s requirements.
  • Airtightness is 5 times better than that required by DIN 4108-2 and is certified to EN 1026:200-09.
  • The hatch also has a U value of 0.58W/m2k certified to EN ISO 12567 – 1: 2001/02. It should be noted that this U value is for a single optimum position in the centre of the door, not the installed value.
  • A Passivhaus-certified option is also available (please get in touch)
Standard Size (size of ceiling opening in cms)
Length 120
Width 60
Height 25
Finished Measurement The finished measurement of the casing is 1.5 cm smaller in length and width than the ceiling.
Attic Ladders The Wellhofer 4D is supplied with a ladder which has a floor to ceiling height of 2570-2680 mm.
U Value 0.58 (not installed value)


A smaller certified airtight pre insulated access hatch is also available (600 x 600mm).

Alternative dimensions are also available on request.

Title Type
Wellhofer Certified Airtight Attic Hatch WS4D Datasheets Download
Wellhofer AIRTIGHT ATTIC HATCH WS4D Technical Drawings 1200 x 600 x 250mm Datasheets Download
Installation Guide Wellhofer Attic Hatch Datasheets Download
Additional Guidance Attic Hatch Installation Datasheets Download

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